You have seen two patterns on the test bench. First, check one:
The voltage across a buzzer rises. The buzzer is unchanged. What happens to the current?
Increasing the voltage across a component increases the current through it. Increasing the resistance decreases the current. One equation ties the two patterns together.
Back at the test bench: a 12 V battery drives a 24 Ω resistor, and the ammeter reads 0.50 A.
Look at the three numbers: 12 divided by 24 is 0.50. The voltage divided by the resistance gives the current.
Careful with the symbols: capital V stands for voltage. Lowercase v stands for speed. This course never swaps them.
Which equation is Ohm's law?
The equation carries the first bench pattern: increase the voltage V, with R unchanged, and the current I increases. It carries the second pattern too: increase the resistance R, with V unchanged, and the current I decreases.
It also fixes the amounts.
The voltage across a fixed resistor is doubled. Use Ohm's law to say what happens to the current.
Ohm's law: I = V/R.
V doubles, and R is unchanged.
So V/R doubles.
The current doubles.
The units match the equation: amperes = volts ÷ ohms. And this course writes Ohm's law with I as the subject, because the current is the thing that responds. The voltage and the resistance set it.
The voltage across a fixed resistor is halved. By Ohm's law, what happens to the current?
A circuit's resistance is tripled; the voltage is unchanged. What does Ohm's law predict for the current?
A line from the speed topic reads v = 3.0 m/s. In I = V/R, which quantity does the capital V stand for?
Capital V and lowercase v stand for different quantities. Which pairing is correct?